OpenSandbox: Instructions file for Claude Code

CLAUDE.md

OpenSandbox CLAUDE.md is an instructions file for Claude Code from opensandbox-group/OpenSandbox. It costs 21 tokens per session, scanned A, original, Apache-2.0.

Repository instructions for OpenSandbox, a software project. They point the coding agent to AGENTS.md for the project's complete rules and conventions.

In plain words
What is it for?
Following OpenSandbox's coding rules, file-routing instructions, and conventions while working on the project.
Why use it?
They give the agent a central place to find project-specific guidance instead of guessing how the repository should be changed.

Instructions file for Claude Code

Written for Claude Code: the file is CLAUDE.md. Also seen: mentions AGENTS.md.

This is opensandbox-group/OpenSandbox's own configuration. It tells Claude Code how to work on OpenSandbox itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything OpenSandbox configures →

About the project

OpenSandbox is a sandbox platform that gives AI applications APIs, SDKs, and runtimes for creating isolated environments, running commands, and managing files. It is used for coding and GUI agents, browser automation, code execution, agent evaluation, and reinforcement-learning training across Docker and Kubernetes environments. The catalogue entries provide instructions and a skill for working with these sandboxes.

opensandbox-group/OpenSandbox · 16,463 stars · on GitHub · open-sandbox.ai

Reuse

Borrowing it

Nothing to install: this file belongs to opensandbox-group/OpenSandbox. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/opensandbox-group/OpenSandbox/main/CLAUDE.md
Clone the repo
git clone --depth 1 https://github.com/opensandbox-group/OpenSandbox

Made for: Claude Code.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for OpenSandbox CLAUDE.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/opensandbox-group/opensandbox/claude-md/github.svg)](https://agentmods.dev/instructions/opensandbox-group/opensandbox/claude-md)
Your own site
<a href="https://agentmods.dev/instructions/opensandbox-group/opensandbox/claude-md"><img src="https://agentmods.dev/badge/instructions/opensandbox-group/opensandbox/claude-md/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for OpenSandbox CLAUDE.md

Your own site · 80×15
<a href="https://agentmods.dev/instructions/opensandbox-group/opensandbox/claude-md"><img src="https://agentmods.dev/badge/instructions/opensandbox-group/opensandbox/claude-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 21 This file is loaded in full into every session.
When invoked 21 The same file — it is already loaded in full.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00021 $0.00021
Opus 5.5 $0.00008 $0.00008
Sonnet 5.5 $0.00004 $0.00004
Haiku 4.5 $0.00002 $0.00002

Measured 2mo ago against content hash fd9b34bd4f0f, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

OpenSandbox CLAUDE.md scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2mo ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

CLAUDE.md · 4 lines

What it actually says

OpenSandbox Claude Guide

See AGENTS.md for all rules, routing, and conventions.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 2mo ago First seen · 4 lines · 21 tokens per session scan A fd9b34bd4f0f

Subscribe to this mod's changes

OpenSandbox CLAUDE.md is an instructions file published in the GitHub repository opensandbox-group/OpenSandbox (16,463 stars, last pushed today), licensed Apache-2.0. It adds 21 tokens to every session, about $0.0001 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

Related

OpenSandbox CLAUDE.md compared with instructions from other repositories

OpenSandbox CLAUDE.md next to 6 instructions from other repositories
ModTypeStarsLast pushLicenceScanTokensWorks with
OpenSandbox CLAUDE.mdopensandbox-group/OpenSandboxInstructions file16ktodayApache-2.0A21Claude Code
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next.js AGENTS.mdvercel/next.jsInstructions file143ktodayMITA7,461Codex, OpenCode
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vscode oss-third-party-notices.instructions.mdmicrosoft/vscodeInstructions file195kyesterdayMITA5,516GitHub Copilot
vscode copilot-instructions.mdmicrosoft/vscodeInstructions file195kyesterdayMITA3,093GitHub Copilot
deepseek-harness AGENTS.mddeepseek-ai/deepseek-harnessInstructions file274k2d agoMITA4,313Codex, OpenCode